Ejector for food supporting elements



Nov. 22, 1960 M. ZWARYCZ EJECTOR FOR FOOD SUPPORTING ELEMENTS Filed May27, 1959 0 -10 up nu up up INVENTOR MICHAEL ZWARYCZ ATTORNEY UnitedStates EJECTOR FOR FOOD SUPPORTING ELEMENTS Filed May 27, 1959, Ser. No.816,263

'7 Claims. (CI. 53-53) This invention relates to improvements in packagewrapping machinery and it is the general object of the invention toprevent the wrapping head of such machinery from being damaged bydelivery to it of empty or unloaded food supporting elements, such asheavy cardboard.

In a known form of wrapping machinery articles to be wrapped, such forinstance as a group of frankfurters, are deposited on comparativelyheavy cardboards which are located along a conveyor which moves eachcardboard and its article to the wrapping head of the machine. The cardsmay be delivered to the conveyor either manually or by machine, and thearticles of food are generally placed by hand on the cardboards as theypass one or more loading points. Occasionally a card will pass theloading point or points without having an article placed on it, andunless such a card is removed from the conveyor it is likely to bedelivered to the elevator mechanism of the wrapping machine and in oneway or another become entangled with the mechanism of the wrap ping headand cause damage.

It is an important object of the present invention to provide means forremoving an unloaded cardboard or food supporting element from theconveyor to prevent damage to the Wrapping head of the machine.

As the cardboards and their articles move toward the wrapping head theypass through a sensing and ejector station and it is a. further objectof the invention to provide sensing means located at the stationeifective to permit a loaded element to pass along tothe wrapping headbut also effective to remove an unloaded; element whilev it is still atthe ejecting station.

It; isa more particular object of the invention to provide a rotatingremoval or ejector wheel mounted in such manner that it tends to movetoward ejecting position and is permitted to do so if the-cardboardelement is unloaded but isprevented from doing so if the sensing meansdetects; thepresence of an article on the element. The sensing meanscontrols lock which in turn controls the tendency of the rotating wheelto move tocard ejecting position.

Itis another object of: the invention to; mount the aforesaid rotatingejector; wheel on a leven operated by a cam; in suchmanner thatthe wheelis moved positively away from; ejecting position; but is urged toward:ejecting position by a spring which can yield in the eventthat theejector wheel should engage two or more cardboards depositediby mistakeneoVer'the; other on theconveyor.

It: is a, further objectof the invention to mount the aforesaid ejectorwheelronthe upper end of a lever. which swings. about. a pivotlocatedbelow butjtozoneside of'the conveyor sothat as the ejector wheelmoves-toward the sensing station it: will havea downward motion'sdue tothe location. of.- the pivot of the lever and be brought intoengagementtwith: the top of an unloaded cardboard element; to remove it.

In. ordenthat; the invention: may be: clearly. understood atentreference is made to the accompanying drawings which illustrate by wayof example the embodiments of the invention and in which:

Fig. l is a side elevation of a portion of the conveyor of a wrappingmachine showing the invention applied thereto and 11'] such position asto eject an unloaded cardboard element,

Fig. 2 is a vertical section on line 2-2, Fig. 1,

Fig. 3 is a detail plan view looking in the direction of arrow 3, Fig.2,

Figs. 4 and 5 are detail operating views having the ejector wheelmounted in two positions relative to the carrier lever, and

Fig. 6 is a diagrammatic view showing the wrapping head of the wrappingmachine on which the invention is used.

Referring more particularly to Fig. 1, the frame of the conveyor systemof the machine supported in any approved manner is indicated at 1 andhas supporting upwardly facing flat runs 2 and 3 between which moveconveyor chains 4. The chains are joined by upwardly extending pushers 5which are equally spaced along the length of the chains 4. In normaloperation the conveyor coacting with runs 2 and 3 will move an article Fof food, shown herein as a group of frankfurters resting on a thin flatcardboard supporting element E, along the runs 2 and 3 and within theouter edges thereof toward the wrapping head WH, Fig. 6, of the machine.As the articles and elements move along the runs and the conveyordesignated generally at C they pass through a sensing and ejectingstation designated generally at S where the presence or absence of anarticle F can be detected by a sensing means designated at D. In Fig. 1three elements E are shown, the ones at the right and left-hand ends ofthe conveyor are shown as being properly loaded with articles F, but thecenter element is shown as unloaded and must be ejected.

The sensing means D includes two uprights 10 and 11 secured to the frame1 and having rockably mounted in their upper ends a sensing shaft 12.Secured to the shaft between the uprights is an arm 13 which as shown inFig. 1 extends to the right and has mounted thereon for free rotation asensing or detecting circular disc 14. The right-hand end of the shaft12, Fig. 2, has securedthereto an arm 15 which is'pivotally connected toa descending link 16 thelower end of which is pivotally connected to onearm of abell crank lever 17 pivoted at 18 to fixed bar 19 mounted aswill be described hereinafter. Another link 20 pivotally connects theother arm of the bell crank lever to a lock lever 21 pivoted at 22 tobar 19 and having a locking detent 23 formed in the upper end thereof.

The operation of the sensing mechanism D is such that the disc 14% isnormally in low position in the path of travel of an article as shown inFig. l and when an article isabsent from the station the discremain'sdown on the cardboard element E at the sensing station. The liftlink 16 is therefore raised andthe lock lever 21 will be in theposition" shown in Fig. 1, which is its nonlock ing. position; It isthis position of the lock lever, as Willbe described hereinafter, whichefiects ejection of the element E from' the sensing and ejectingstation. A torsion spring 24' surrounding part of shaft 12 urges thedisc l4tdownwa'rdly' and tends to hold" lock 21 normally inunlocking"position. Downward motion of the disc is limitedby engagement of a pin 6on upright 11 with a short lever rockable with sensing" shaft 12.

Bolted at 25 to one of the vertical sidesof the frame 1 is the foot 26of a support or stand having right and left depending. arms 27 and 28respectively as viewed in Fig,- l. Bar 19 is secured to the lower endsof these arms 27 and 28. Journaled in these arms is a driving shaft 29which has secured to the left end thereof as viewed in Fig. 1 a bevelgear 30 which is driven in any approved manner from a source of power(not shown) to rotate the shaft once for each operating cycle of themachine. The shaft 29 has secured thereto a sprocket wheel 31 which bymeans of a chain 32 drives lower sprocket 33 fastened to a driven shaft34 journaled in the lower ends of arms 27 and 28.

The shaft 34 has secured thereto a sprocket wheel 35 which by means of achain 36 has driving relation with a sprocket wheel 37 secured to a stubshaft 38 rotatable in bearings 54 on the forked upper end of a carrierlever 39. The latter lever swings about the shaft 34 as a center and hasrotatable thereon a roll 40 which engages a cam 41 secured to thedriving shaft 29 and which normally controls lever 39. A pull spring 42having its left-hand end as viewed in Fig. 2 fastened to a dependingstud 43 fixed to the conveyor frame has its right-hand end fastened to astud or the like 44 on the lever 39 and tends to move lever 39 towardthe conveyor and also tends to hold the roll against the cam.

The cam has a high dwell 45 and a low dwell 46 connected to it byinclines 47. When the previously mentioned lock lever 21 is in itsunlocking position the roll 40 can move from the high dwell 45 down oneof the inclines 47 to the low dwell 46 to permit the spring 42 to movethe lever from its nonejecting position shown in Fig. 2 to the left toits ejecting position. If, on the other hand, the lock lever 21 is inits locked position so that the detent 23 engages a lock lug 50 securedto the lever the lock will hold the roll 40 away from the cam as anincline arrives under it and the lever will remain in its nonejectingposition during an interval of stoppage of the conveyor chain.

Mounted on the upper end of the lever 39 is a bodily movable ejectormechanism shown in Fig. 3 and designate-d generally at 55. Thismechanism comprises a lever 56 mounted for slight rockable motion aboutthe previously mentioned shaft 38 which is rotatable on the upper end oflever 39. Lever 56 has a hub 58 in which the shaft 38 turns and thelatter shaft has secured thereto a sprocket wheel 59 which by a chain 60drives a sprocket wheel 61 pinned as at 62 to an ejector shaft 63rotatable in another hub bearing 64 formed on the lever 56. A sidebearing arm 65 of lever 56 provides additional support for lever 56 onshaft 38.

The ejector which actively discharges an unloaded element E from theconveyor comprises a wheel made preferably of rubber and bonded to a hub71 which is held by set screw 72 on the ejector shaft 63. An idlersprocket 75 rotatable on a stud 76 held by a small stand 77 fastened at78 to the lever 56 keeps the chain 60 taut. As long as the shaft 38 isturned by power derived from the shaft 29 and transmitted through thechains and the sprockets already described the ejector Wheel 70 willrotate without regard to the position of the lever 39.

The lever 56 has a depending arm 80 which cooperates with a limitingscrew 81 to permit a slight angular motion of the lever 56 with respectto the lever 39. The limiting screw 81 has thereon nuts 82 and 83engaging opposite sides of the lever 39 for adjustment relative to thelatter and the screw has a head 84 normally spaced from the arm 80, thelatter being held against the nut 83 by the weight of the lever 56 andthe parts mounted thereon. Arm 80 has a hole 85 therein for screw 81large enough to allow free motion of lever 56. The reason for theangular motion of lever 56 is to permit it to move from the position ofFig. 4 to the position of Fig. 5 to take care of any excess motion oflever 39 which might occur after roll 70 engages an element E.

It will be noted from Fig. 2 that the horizontal shaft 34 around whichlever 39, lever 56 and roll 70 turn is below and spaced considerably toone side of the conveyor chains and the runways 2 and 3. It is becauseof the location of the shaft 34 that rocking motion of the lever 39 tothe left from the position shown in Fig. 2 causes the roll 70 to descendtoward the path of travel of the elements along the conveyor onto thetop of an unloaded element E at station S and remove it in a directionto the right as viewed in Fig. 2.

When a cardboard element E is ejected it moves in a direction at rightangles to the travel of the conveyor and slides down a chute 86 to areceiver (not shown). The ejected elements are not damaged by theejector wheel 70 and can be reused.

It is believed that the operation of the mechanism will be understoodfrom the previous description but it may be stated that when an articleF on a cardboard element E arrives at the sensing station the disc 14will be raised to move the locking lever 21 to its locking position sothat the detent 23 will engage the locking stud 50 and prevent angularmotion of the lever 39 to the left as viewed in Fig. 2 when a decline ofthe cam arrives under the roll 40. At this time the conveyor chain is atrest for an interval of time and the article F will hold disc 14 upwhile the declines and low dwell of the cam pass by roll 40 and spring24 will not be able to unseat the lock lever 21 from the stud 50. If, ontheother hand, an article F should be absent from the element E uponarrival of the latter at the station S the disc 14 will remain down byaction of the torsion spring 24 to hold the lock lever 21 in itsunlocking position, whereupon the roll 40 can travel along a decline ofthe cam and the ejector roll 70 will descend against the top surface ofthe unloaded element E and eject it. Further turning of the cam willrestore the lever 39 to the position shown in Fig. 2.

The conveyor chain 4 is operated intermittently by means not shown tostop the pushers one at a time in position to locate the elements E andarticles F at the sensing or ejecting station S. After the ejector wheel79 has had time to move to ejecting position and return to normalposition in transverse alignment with the ejecting station and above andto one side of the conveyor, if that is necessary, the chain will moveagain to place the next article F at the station and then stop. The highdwell 45 of cam 41 holds the lever 39 and roll 70 in nonejectingposition while the conveyor is moving, and the inclines 47 and low dwell46 permit roll 70 to move to and back from ejecting position, ifnecessary, while the conveyor is momentarily at rest.

At one end of the conveyor there is located the wrapping head WH of thewrapping machine. The head has a plunger system and a guide former 111having an opening 112 for the article to be wrapped. A sheet wrapper Wis supplied in usual manner over the system 110 and the article to bewrapped. The plunger system rises to push the article and sheet upthrough the opening 112 and then descends for the next operation, all inknown manner. The conveyor chain and pushers 5 move an article and itscardboard element to the wrapping head and if the element is empty itmay damage the head. The latter and the parts associated with it areshown diagrammatically in Fig. 6, much of the detail being omitted sincethe head is of well known construction.

From the foregoing it will be seen that the invention provides elementejecting means located at a station along the conveyor and has placingmeans, such as cam 41 and spring 42, tending at periodic intervals whenthe conveyor is at rest to move the ejecting means to ejecting position,but is prevented from doing so by control means, such as sensing disc 14and lock 21, if an article is on the element at the station. If anarticle is absent the control means permits the ejecting means to followits normal tendency and move against the element and remove it, therebypreventing the element from reaching and possibly damaging the wrappinghead WH. The ejecting means includes the constantly rotating wheel 70which, because of the location of shaft 34 with respect to the conveyor,moves down to engage the top of the article and move the latter towardthe chute 85. The ejector operating shaft 38 has operative connections,such as chain 60, with the ejector 70 to cause the latter to be rotatedby power derived from shaft 29. The low position of the sensing disc 14is determined by a stop 6, Figs. 1 and 2, which engages a stop arm 7secured to shaft 12. This stop also determines the position of locklever 21.

Having now particularly described and ascertained the nature of theinvention and in what manner the same is to be performed, what isclaimed is:

1. In protector mechanism for the wrapping head of a wrapping machine, aconveyor coacting with a run on each side thereof operative to supportand transport thin flat article support elements within the outer edgesof the runs to an ejecting station and toward said head, each elementnormally provided with an article thereon to be wrapped therewith atsaid head but being capable of damaging the head if delivered thereto bythe conveyor without an article thereon, a bodily movable elementejector wheel continuously rotating during operation of the machine andnormally above and to one side of the conveyor and in transversealignment with said station, periodically acting placing cam meanstending to move the ejector into ejecting relation with respect to anelement on the conveyor at the ejecting station, vertically movablesensing means at said station and normally down and in the path oftravel of an article to determine whether or not an article is on anelement at the ejecting station, and locking means for the placing meansand normally in unlocked relationship with the placing means andoperated by the sensing means when the latter moves upwardly toestablish locking relationship between the locking and placing means,the sensing means when sensing the presence of an article on an elementat the ejecting station effective by upward movement to prevent theplacing means from moving the ejector into ejecting relation with theelement but when in down position enabling the placing means because ofsaid unlocked relationship to move the ejector into ejecting relationwith the element to remove the latter from the conveyor in the event ofabsence of an article on the element.

2. The protector mechanism set forth in claim 1 wherein the ejectorwheel is above the conveyor and runs in transverse relationship theretoand is mounted on a vertical carrier lever movable by the placing meansabout a pivot below and out of vertical alignment with the conveyor,whereby arcuate movement of the lever moves the ejector down on anelement at the station to eject it when an article is absent at thestation.

3. The protector mechanism set forth in claim l where in the conveyormoves the element along a path while lying flat on the conveyor and theplacing cam means moves the ejector wheel about a horizontal axis andcauses the ejector wheel to move in a vertical plane down toward thepath to engage the top of an element at the station to remove theelement by a motion transverse of the conveyor, provided there is noarticle on the element.

4. The protector mechanism set forth in claim 1 wherein the carrierlever is moved by a spring to be normally against the cam and a part onthe lever is locked by the locking means to prevent the spring frommoving the ejector against an element at said station when an article ispresent on the element.

5. The protector mechanism set forth in claim 4 wherein the bodilymovable ejector is mounted for limited free motion with respect to saidcarrier lever enabling the ejector to have motion relative to the levershould the latter have excess motion subsequent to engagement of theejector with an element.

6. In protector mechanism for the wrapping head of a wrapping machine, aconveyor including a run on each side thereof operative to support andtransport thin flat article supporting elements within the outer edgesof the runs to an ejecting station and toward said head, each elementnormally provided with an article thereon to be wrapped therewith atsaid head but being capable of damaging the head if delivered thereto bythe conveyor without an article thereon, a shaft below and to one sideof the conveyor and which rotates when the machine is in operation, avertical lever pivoted about the axis of said shaft and capable ofmoving to ejecting and nonejecting positions, an element ejector wheelrotatably mounted on the lever for constant rotation during machineoperation, a rotatable cam having high and low dwells driven from saidshaft effective at periodic intervals to normally move the lever tononejecting position by reason of said high dwell, a spring normallyholding the lever against the cam and moving the lever to ejectingposition between said intervals by reason of said low dwell, means torotate the ejector wheel from said shaft, and a lock normally inunlocking position for the lever capable of being in locking orunlocking position relative to the lever and effective if an article ispresent on an element at the station to be moved to locking position andprevent the spring from moving the ejector wheel into element ejectingposition but being in unlocking position if an article is absent fromthe station and enabling the spring to move the lever to place theejector wheel in element ejecting position.

7. The mechanism set forth in claim 6 wherein the lever has an ejectoroperating shaft constantly rotating thereon during machine operation anddriven from the first named shaft and the ejector operating shaft haschain and sprocket operative connections with the ejector wheel toconstantly rotate the latter by power derived from the first named shaftand transmitted to the shaft on the lever.

References Cited in the file of this patent UNITED STATES PATENTS2,029,933 Milmoe Feb. 4, 1936 2,622,518 Peterson et al. Dec. 23, 19522,921,421 Ouellette et al. Jan. 19, 1960 FOREIGN PATENTS 386,955 GreatBritain 1933 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTIONPatent No 2,960,809 November 22, 1960 Michael Zwarycz It is herebycertified that error appears in the above numbered patent requiringcorrection and that the said Letters Patent should read as correctedbelow.

In the grant, lines 2 and 12, and in the heading to the printedspecification, lines 3 and 4, name of assignee, for 'Crompton 8: KnowlesPacking Corporation", each occurrence, read Crompton 81 KnowlesPackaging Corporatlon Signed and sealed this 13th day of June 1961.

(SEAL) attest:

ERNEST W. SWIDER DAVID L. LADD Xttesting Officer Commissioner of Patents

